SPP Pumps
2905 Pacific Drive
Norcross, GA 30071

Phone: +1 (770) 409-3280
Fax: +1 (770) 409-3290

 
 
 
 
 
  Frequently Asked Questions

1.   What are the differences in all of the starting methods used in fire pump electric controllers?
   
  • Starting Methods
     
2.   What is locked rotor amps?
   
  LRA is 6 times full load amps.
     
3.   What is AIC rating?
   
  Ampacity Inrush Current. It refers to the rating of a fire pump controller enclosure to protect from electric surges.
     
4.   Why are there tier levels for diesel engines, and what do they mean?
   
  EPA requires for all fire pump engines to comply with EPA tier 3 emissions standards for engines sold in the US and its territories. All engines sold outside the US are not subject to this requirement. In addition, any engine running over 2650 rpm is not subject to these standards in any part of the world including US, except California. until 2012.
     
5.   What are the differences in NEMA enclosure ratings?
   
  • NEMA Enclosure Types
     
6.   How do I figure out my churn pressure?
   
  Churn pressure is pump pressure at 0 flow, plus static suction pressure from supply source.
     
7.   What is the difference between clockwise and counterclockwise rotation of a fire pump?
   
  If you are sitting on the motor, looking at the pump, if the water supply is on your right, that is clockwise (right hand rotation). If the supply water is on your left, that is Counter clockwise (left hand rotation). Typically, your suction flange will be greater than your discharge flange.
     
8.   What are the differences between ODP and TEFC motors?
   
  Open Drip Proof, typically used in indoor applications or Totally Enclosed, Fan Cooled, typically used in outdoor applications.
     
9.   What is an Automatic Air Release Valve and a Casing Relief Valve?
   
  Automatic air release valve is used on Horizontal split case pumps and is installed at the top of the casing to prevent air getting trapped in the pump casing causing cavitation and other issues that will cause internal damage.
     
  Casing relief valve (circulation valve) is used on HSC, VIL and End suction pumps to allow cool water from the discharge side of the pump to circulate through the casing to prevent pump from overheating. In a diesel application, a CRV is not required because the cooling loop accomplishes the same task.
     
10.   When would I require a Main Relief Valve?
   
  On diesel applications where pump shut of pressure (0 flow) plus suction pressure times 121% is greater than the rated system pressure, a main relief valve shall be required. Main relief valves for electric sets violate NFPA 20 code.
     
11.   How often do I need to test my fire pump?
   
  NFPA requires weekly testing on all fire pumps.
     
12.   How should I size a jockey pump (Pressure Maintenance Pump)?
   
  NFPA 20 suggests that the jockey pump be sized 1% of pump flow at 10 psi over pump rated pressure.
     
   

 

 

 

 
     
 

SPP PUMPS INC.